Display device and method of manufacturing the same

ABSTRACT

A display device includes a display panel, a protective film, and an adhesive member. The display panel includes a non-bending area and a bending area configured to bend from the non-bending area, and the bending area includes a curvature area with a curvature and a facing area facing the non-bending area. The protective film is on a rear surface of the display panel, and includes a first surface facing the rear surface of the display panel and a second surface opposite to the first surface. The protective film has a groove corresponding to the curvature area. The adhesive member is between the protective film and the display panel, and a hydrophobic layer is on the second surface of the protective film, and is adjacent to the groove.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2018-0062265, filed on May 31, 2018, the entirecontent of which is hereby incorporated by reference in its entirety.

BACKGROUND 1. Field

The present disclosure relates to a display device and a method ofmanufacturing the same. More particularly, the present disclosurerelates to a display device having improved bending characteristic and amethod of manufacturing the display device.

2. Description of the Related Art

Electronic devices, such as a smartphone, a tablet computer, a notebookcomputer, and a smart television, have been developed. The electronicdevices include display devices to provide information. The electronicdevices further include a variety of electronic modules in addition tothe display devices.

The display device included in the electronic device may be partiallybent to implement a slim bezel.

SUMMARY

This summary is provided to introduce a selection of features andconcepts of embodiments of the present disclosure that are furtherdescribed below in the detailed description. This summary is notintended to identify key or essential features of the claimed subjectmatter, nor is it intended to be used in limiting the scope of theclaimed subject matter. One or more of the described features may becombined with one or more other described features to provide a workabledevice.

Some example embodiments of the present disclosure provide a displaydevice having improved bending characteristic.

Some example embodiments of the present disclosure provide a method ofmanufacturing the display device.

Some example embodiments of the inventive concept provide a displaydevice including a display panel, a protective film, and an adhesivemember.

In some example embodiments, a display panel includes a non-bending areaand a bending area bent from the non-bending area, and the bending areaincludes a curvature area with a set or predetermined curvature and afacing area facing the non-bending area. The protective film is on arear surface of the display panel, and includes a first surface facingthe rear surface of the display panel and a second surface opposite tothe first surface, and is provided with a groove defined thereincorresponding to the curvature area. The adhesive member is between theprotective film and the display panel, and a hydrophobic layer is on thesecond surface of the protective film to be adjacent to the groove.

In some example embodiments, the second surface of the protective filmis divided into a first rear surface and a second rear surface such thatthe groove is disposed between the first and second rear surfaces, andthe protective film further includes a first inner side surfaceextending from the first rear surface to define the groove and a secondinner side surface extending from the second rear surface to define thegroove.

In some example embodiments, the hydrophobic layer includes a firsthydrophobic layer on the first rear surface to be adjacent to the firstinner side surface and a second hydrophobic layer on the second rearsurface to be adjacent to the second inner side surface.

In some example embodiments, the groove extends in a first direction,and each of the first and second hydrophobic layers extends along thefirst direction.

In some example embodiments, the first hydrophobic layer and the secondhydrophobic layer face each other.

In some example embodiments, the hydrophobic layer includes one ofmanganese oxide (MnO2) polystyrene, zinc oxide (ZnO) polystyrene,precipitated calcium carbonate, carbon nanotube, silica, andfluoropolymer.

Some example embodiments of the inventive concept provide a method ofmanufacturing a display device including a preliminary display deviceincluding a display panel including a first area and a second areaconnected to the first area, an adhesive member on a rear surface of thedisplay panel, and a preliminary protective film including a firstsurface on which a rear surface of the adhesive member is disposed,forming a preliminary hydrophobic layer on a second surface of thepreliminary protective film, which faces the first surface of theprotective film, to correspond to the second area, pressing theprotective film and the preliminary hydrophobic layer using a heatingblock such that a portion of the protective film corresponding to aportion of the second area is removed to form a groove and to divide thepreliminary hydrophobic layer into first and second hydrophobic layersby the groove, the removed portion of the protective film being formedas first and second bumps on an upper surface of the first and secondhydrophobic layers, respectively, removing the first and second bumpsformed on the upper surface of the first and second hydrophobic layers,and bending the second area.

In some example embodiments, the first and second bumps are removed byusing an air spray device spraying air.

In some example embodiments, the first hydrophobic layer and the secondhydrophobic layer face each other when the second area is bent.

Some example embodiments of the inventive concept provide a method ofmanufacturing a display device including a preliminary display deviceincluding a display panel including a first area and a second areaconnected to the first area, an adhesive member on a rear surface of thedisplay panel, and a protective film including a first surface on whicha rear surface of the adhesive member is disposed, forming first andsecond sub-grooves in a second surface of the protective film, whichfaces the first surface of the protective film, to overlap with thesecond area, pressing the protective film using a heating block suchthat a portion of the protective film corresponding to a portion betweenthe first and second sub-grooves is removed to form a groove, theremoved portion of the protective film, which is collected in the firstand second sub-grooves being formed as first and second bumps, andbending the second area.

In some example embodiments, the second surface of the protective filmis divided into a first rear surface and a second rear surface such thatthe groove is disposed between the first and second rear surfaces, andthe protective film further includes a first inner side surfaceextending from the first rear surface to define the groove and a secondinner side surface extending from the second rear surface to define thegroove.

In some example embodiments, the first sub-groove is formed between thefirst rear surface and the first inner side surface, and the secondsub-groove is formed between the second rear surface and the secondinner side surface.

In some example embodiments, the groove extends in a first direction,and each of the first and second sub-grooves extends in the firstdirection along the groove.

In some example embodiments, the first and second sub-grooves are formedin the second surface through a blanking process.

In some example embodiments, the first bump and the second bump faceeach other when the second area is bent.

In some example embodiments, the display device may reduce theinterference due to the bumps around the curvature area of the displaypanel.

According to some example embodiments of the manufacturing method of thedisplay device, because the bumps are removed or the size of the bumpsis reduced during the bending process, a design margin of the displaydevice may be secured.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the present disclosure will becomereadily apparent by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings wherein:

FIG. 1 is a perspective view showing an electronic device, according toan exemplary embodiment of the present disclosure;

FIG. 2 is an exploded perspective view showing a display device,according to an exemplary embodiment of the present disclosure;

FIG. 3 is a side view showing the display device of FIG. 2, according toan exemplary embodiment of the present disclosure;

FIG. 4 is a side view showing a bent state of the display device shownin FIG. 3, according to an exemplary embodiment of the presentdisclosure;

FIG. 5 is a partially enlarged cross-sectional view of a display moduleshown in FIG. 3, according to an exemplary embodiment of the presentdisclosure;

FIG. 6 is a rear view of the display module shown in FIG. 5, accordingto an exemplary embodiment of the present disclosure;

FIG. 7 is a perspective view showing a heating block, according to anexemplary embodiment of the present disclosure;

FIGS. 8A to 8D are side views showing a method of manufacturing adisplay device, according to an exemplary embodiment of the presentdisclosure;

FIG. 9 is a side view showing a display device, according to anotherexemplary embodiment of the present disclosure;

FIG. 10 is a side view showing a bent state of the display device shownin FIG. 9, according to an exemplary embodiment of the presentdisclosure;

FIGS. 11A to 11C are cross-sectional views showing a method ofmanufacturing the display device shown in FIG. 9, according to anexemplary embodiment of the present disclosure;

FIG. 12A is a perspective view of FIG. 11A, according to an exemplaryembodiment of the present disclosure; and

FIG. 12B is a perspective view of FIG. 11C, according to an exemplaryembodiment of the present disclosure.

DETAILED DESCRIPTION

The present disclosure may be variously modified and realized in manydifferent forms, and thus specific embodiments will be exemplified inthe drawings and described in detail hereinbelow. However, the presentdisclosure may not be limited to the specific disclosed forms, and beconstrued to include all modifications, equivalents, or replacementsincluded in the spirit and scope of the present invention.

It will be understood that the terms “includes” and/or “including”, whenused in this specification, specify the presence of stated features,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. In addition, It will be understood that when a layer, film,area, or plate is referred to as being “on” another layer, film area, orplate, it can be directly on the other layer, film, area, or plate orintervening layers, films, areas, or plates may be present. In contrast,when a layer, film, area, or plate is referred to as being “below”another layer, film area, or plate, it can be directly below the otherlayer, film, area, or plate or intervening layers, films, areas, orplates may be present.

Like numbers refer to like elements throughout. In the drawings,structures are exaggerated for clarity. It will be understood that,although the terms first, second, etc. may be used herein to describevarious elements, components, regions, layers and/or sections, theseelements, components, regions, layers and/or sections may not be limitedby these terms. These terms are only used to distinguish one element,component, region, layer or section from another region, layer orsection. Thus, a first element, component, region, layer or sectiondiscussed below could be termed a second element, component, region,layer or section without departing from the teachings of the presentinvention. As used herein, the singular forms, “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise.

It will be understood that, although the terms “first”, “second”,“third”, etc., may be used herein to describe various elements,components, regions, layers and/or sections, these elements, components,regions, layers and/or sections should not be limited by these terms.These terms are only used to distinguish one element, component, region,layer or section from another element, component, region, layer orsection. Thus, a first element, component, region, layer or sectiondiscussed herein could be termed a second element, component, region,layer or section, without departing from the spirit and scope of theinventive concept.

Spatially relative terms, such as “beneath”, “below”, “lower”, “under”,“above”, “upper” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. It will beunderstood that such spatially relative terms are intended to encompassdifferent orientations of the device in use or in operation, in additionto the orientation depicted in the figures. For example, if the devicein the figures is turned over, elements described as “below” or“beneath” or “under” other elements or features would then be oriented“above” the other elements or features. Thus, the example terms “below”and “under” can encompass both an orientation of above and below. Thedevice may be otherwise oriented (e.g., rotated 90 degrees or at otherorientations) and the spatially relative descriptors used herein shouldbe interpreted accordingly. In addition, it will also be understood thatwhen a layer is referred to as being “between” two layers, it can be theonly layer between the two layers, or one or more intervening layers mayalso be present.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the inventiveconcept. As used herein, the terms “substantially,” “about,” and similarterms are used as terms of approximation and not as terms of degree, andare intended to account for the inherent deviations in measured orcalculated values that would be recognized by those of ordinary skill inthe art.

As used herein, the term “and/or” includes any and all combinations ofone or more of the associated listed items. Expressions such as “atleast one of,” when preceding a list of elements, modify the entire listof elements and do not modify the individual elements of the list.Further, the use of “may” when describing embodiments of the inventiveconcept refers to “one or more embodiments of the present invention”.Also, the term “exemplary” is intended to refer to an example orillustration. As used herein, the terms “use,” “using,” and “used” maybe considered synonymous with the terms “utilize,” “utilizing,” and“utilized,” respectively.

It will be understood that when an element or layer is referred to asbeing “on”, “connected to”, “coupled to”, or “adjacent to” anotherelement or layer, it may be directly on, connected to, coupled to, oradjacent to the other element or layer, or one or more interveningelements or layers may be present. In contrast, when an element or layeris referred to as being “directly on”, “directly connected to”,“directly coupled to”, or “immediately adjacent to” another element orlayer, there are no intervening elements or layers present.

The electronic or electric devices and/or any other relevant devices orcomponents according to embodiments of the present invention describedherein may be implemented utilizing any suitable hardware, firmware(e.g. an application-specific integrated circuit), software, or acombination of software, firmware, and hardware. For example, thevarious components of these devices may be formed on one integratedcircuit (IC) chip or on separate IC chips. Further, the variouscomponents of these devices may be implemented on a flexible printedcircuit film, a tape carrier package (TCP), a printed circuit board(PCB), or formed on one substrate. Further, the various components ofthese devices may be a process or thread, running on one or moreprocessors, in one or more computing devices, executing computer programinstructions and interacting with other system components for performingthe various functionalities described herein. The computer programinstructions are stored in a memory which may be implemented in acomputing device using a standard memory device, such as, for example, arandom access memory (RAM). The computer program instructions may alsobe stored in other non-transitory computer readable media such as, forexample, a CD-ROM, flash drive, or the like. Also, a person of skill inthe art should recognize that the functionality of various computingdevices may be combined or integrated into a single computing device, orthe functionality of a particular computing device may be distributedacross one or more other computing devices without departing from thespirit and scope of the exemplary embodiments of the present invention.

Although exemplary embodiments of a display device and a method ofmanufacturing the same have been specifically described and illustratedherein, many modifications and variations will be apparent to thoseskilled in the art. Accordingly, it is to be understood that a displaydevice and a method of manufacturing the same constructed according toprinciples of this invention may be embodied other than as specificallydescribed herein. The invention is also defined in the following claims,and equivalents thereof.

Hereinafter, the present invention will be explained in detail withreference to the accompanying drawings.

FIG. 1 is a perspective view showing an electronic device ED, accordingto an exemplary embodiment of the present disclosure.

Referring to FIG. 1, a smartphone is shown as a representative exampleof the electronic device ED, but the electronic device ED may not belimited to the smartphone. In the exemplary embodiment of the presentdisclosure, the electronic device ED may be a tablet computer, anotebook computer, or a smart television.

As shown in FIG. 1, a display surface, through which an image IM isdisplayed, is substantially parallel to a surface defined by a firstdirection axis DR1 and a second direction axis DR2. The display surfacemay include a display area DA and a bezel area BZA adjacent to thedisplay area DA. FIG. 1 shows an internet search window as arepresentative example of the image IM. As an example, the display areaDA may have a quadrangular shape. The bezel area BZA may surround thedisplay area DA. In other words, the bezel area BZA serves as an edge ofthe display surface.

A third direction axis DR3 indicates a normal line direction of thedisplay surface, i.e., a thickness direction of the electronic deviceED. Front (or upper or first) and rear (or lower or second) surfaces ofeach member are distinguished from each other with respect to thedirection in which the image IM is displayed. However, directionsindicated by the first, second, and third direction axes DR1, DR2, andDR3 are relative to each other, and thus the directions indicated by thefirst, second, and third direction axes DR1, DR2, and DR3 may be changedto other directions. Hereinafter, first, second, and third directions,which are respectively indicated by the first, second, and thirddirection axes DR1, DR2, and DR3, will be assigned with the samereference numerals as those of the first, second, and third directionaxes DR1, DR2, and DR3.

The electronic device ED may include a display device DD and an externalcase EDC. The display device DD will be described in detail later.

The external case EDC may be coupled to the display device DD. Theexternal case EDC may provide an external surface of the electronicdevice ED. In the exemplary embodiment, the external case integrallyformed as a single unitary and individual unit (i.e., a single body) isshown as a representative example. However, in some embodiments, theexternal case EDC may include a plurality of bodies assembled to eachother. The external case EDC may include a plurality of frames and/orplates formed of a glass, plastic, and/or metal material.

FIG. 2 is an exploded perspective view showing a display device DD,according to an exemplary embodiment of the present disclosure, FIG. 3is a side view showing the display device DD of FIG. 2, according to anexemplary embodiment of the present disclosure, and FIG. 4 is a sideview showing a bent state of the display device DD shown in FIG. 3,according to an exemplary embodiment of the present disclosure.

As shown in FIG. 2, the display device DD may include a window member WMand a display module DM. The window member WM includes a base member BS(as shown in FIG. 3) and a bezel layer BZL (as shown in FIG. 3) on arear surface of the base member BS. An area in which the bezel layer BZLis disposed may be referred to as the bezel area BZA as shown in FIG. 1.In the present embodiment, the window member WM has a flat shape in thedisplay area DA, however, the shape of the window member WM may varyaccording to embodiments. Edges of the window member WM may be curved.In other words, the window member WM may have a curved surface.

The base member BS may include a glass substrate, a sapphire substrate,or a plastic substrate. The base member BS may have a single ormulti-layer structure. For instance, the base member BS may include aplurality of plastic films coupled to each other by an adhesive. Thebase member BS may include the glass substrate and the plastic filmcoupled to the glass substrate by an adhesive member.

The bezel layer BZL may have a single or multi-layer structure. Thebezel layer BZL having the multi-layer structure may include a bufferlayer for improving an adhesive force, a pattern layer for providing aset or predetermined pattern, and an achromatic layer. The pattern layermay provide a pattern referred to as a hairline pattern. The achromaticlayer may include an organic mixture containing a black pigment or dye.The layers may be formed by a depositing, printing, and/or coatingmethod. Although not shown separately, the window member WM may furtherinclude a functional coating layer disposed on an entire surface of thebase member BS. The functional coating layer may include ananti-fingerprint layer, an anti-reflective layer, and/or a hard coatinglayer.

The display module DM may include a display panel DP, an input sensingunit ISU, an anti-reflective unit ARU, a protective film PF, and/or adriving control module DCM. FIG. 3 shows the display panel DP in anunbent state, and FIG. 4 shows the display panel DP in a bent state.

The display panel DP is a flexible display panel, for example, anorganic light emitting display panel. The display panel DP includes apixel area PXA (as shown in FIG. 2) in which a pixel PX is located, anda non-pixel area NPXA (as shown in FIG. 2) located adjacent to the pixelarea PX when viewed in a plan view. The pixel PX is not in the non-pixelarea NPXA, and peripheral components such as signal lines and banks arein the non-pixel area NPXA. The pixel area PX corresponds to the displayarea DA (e.g., refer to FIG. 1), and the non-pixel area NPXA correspondsto the bezel area BZA (e.g., refer to FIG. 1). However, the areas (forexample, shapes or sizes) corresponding to each other may not becompletely identical.

The input sensing unit ISU may obtain coordinate information of anexternal input. The input sensing unit ISU may sense various inputs fromoutside the electronic device ED. As an example, the input sensing unitISU may sense inputs from a user's body or various types of externalinputs, e.g., light, heat, and/or pressure. In addition, the inputsensing unit ISU may sense not only inputs caused by contact between asensing surface and other objects but also inputs caused by otherobjects approaching the sensing surface.

The anti-reflective unit ARU may include a polarization film and/or aphase retardation film. The number of the phase retardation films and aphase retardation length (λ/4 or λ/2) of the phase retardation film maybe determined according to an operation principle of the anti-reflectiveunit ARU. The anti-reflective unit ARU may include color filters.

Referring to FIGS. 3 and 4, the protective film PF is on a rear surfaceof the display panel DP. In the present exemplary embodiment, a grooveGR is defined in the protective film PF to correspond to a curvaturearea CA. The groove GR may be formed by a heating block HB (e.g., referto FIG. 7). The groove GR is defined by removing at least a portion ofthe protective film PF. Detailed descriptions about processes of formingthe groove GR will be described later.

The protective film PF may include the plastic film as its base layer.The protective film PF may include the plastic film containing oneselected from the group consisting of a thermoplastic resin, such aspolyethyeleneterepthalate (PET), polyethyelene (PE), polyvinylchloride(PVC), polypropylene (PP), polystyrene (PS), polyacrylonitrile (PAN),styrene-acrylonitrile copolymer (SAN), acrylonitrile-butadiene-styrene(ABS), polymethyl methacrylate (PMMA), and combinations thereof. Inparticular, polyethyeleneterepthalate (PET) has superior heatresistance, stress strength, and electrical properties, andpolyethyeleneterepthalate (PET) is less affected by temperature andhumidity.

Materials used to form the protective film PF may not be limited toplastic resins and may include organic/inorganic composites. Theprotective film PF may include a porous organic layer and an inorganicmaterial filled in pores of the organic layer. As an example of thepresent disclosure, the protective film PF may include a hydrophilicmaterial.

The protective film PF includes a first surface FS facing the rearsurface of the display panel DP and a second surface RS opposite to thefirst surface FS. The second surface RS may be defined as a rear surfaceof the protective film PF. The display module DM further includeshydrophobic layers HP1 and HP2 on the second surface RS adjacent to thegroove GR. The second surface RS of the protective film PF may bedivided into a first rear surface RS1 and a second rear surface RS2 suchthat the groove GR is between the first and second rear surfaces RS1 andRS2. The hydrophobic layers HP1 and HP2 may include a first hydrophobiclayer HP1 on the first rear surface RS1 and a second hydrophobic layerHP2 on the second rear surface RS2.

Referring to FIGS. 2-4, the driving control module DCM may include afirst circuit board MCB, a second circuit board FCB connecting the firstcircuit board MCB and the display panel DP, and a driving chip F-ICmounted on the second circuit board FCB. Although not shown separately,a plurality of passive devices and a plurality of active devices may bemounted on the first circuit board MCB. The first circuit board MCB maybe a rigid circuit board or a flexible circuit board, and the secondcircuit board FCB may be a flexible circuit board.

In the present exemplary embodiment, the input sensing unit ISU and theanti-reflective unit ARU are provided separately from the display panelDP, however, at least one of the input sensing unit ISU and theanti-reflective unit ARU may be integrally provided with the displaypanel DP through continuous processes. At least one of the input sensingunit ISU and the anti-reflective unit ARU may be omitted.

The display module DM further includes first, second, third, fourth, andfifth adhesive members AM1 to AM5. Each of the first to fifth adhesivemembers AM1 to AM5 may be a pressure sensitive adhesive film (PSA), anoptically clear adhesive film (OCA), or an optically clear resin (OCR).Each of the first to fifth adhesive members AM1 to AM5 may include alight-curable adhesive material or a heat-curable adhesive material,however, they may not be limited to a specific material. In addition,some of the first to fifth adhesive members AM1 to AM5 may be omitted.

As an example of the present disclosure, the input sensing unit ISU ison a rear surface of the window member WM. The first adhesive member AM1is located between the window member WM and the input sensing unit ISU,and the window member WM and the input sensing unit ISU may be coupledto each other by the first adhesive member AM1.

The anti-reflective unit ARU is on a rear surface of the input sensingunit ISU. The second adhesive member AM2 is located between the inputsensing unit ISU and the anti-reflective unit ARU, and the input sensingunit ISU and the anti-reflective unit ARU may be coupled to each otherby the second adhesive member AM2.

The display panel DP is on a rear surface of the anti-reflective unitARU. The third adhesive member AM3 is located between theanti-reflective unit ARU and the display panel DP, and theanti-reflective unit ARU and the display panel DP may be coupled to eachother by the third adhesive member AM3. As an example of the presentdisclosure, the third adhesive member AM3 may be relatively thinner(i.e., has relatively less thickness) than that of the first adhesivemember AM1 and the second adhesive member AM2. As another example of thepresent disclosure, positions of the anti-reflective unit ARU and theinput sensing unit ISU may be changed with respect to each other.

In FIGS. 3 and 4, for the convenience of explanation, the display panelDP is shown as a single layer, however, the display panel DP in thediscussed embodiment includes plural layers.

FIG. 5 is a partially enlarged cross-sectional view of the displaymodule shown in FIG. 3, according to an exemplary embodiment of thepresent disclosure, and FIG. 6 is a rear view the display module shownin FIG. 5, according to an exemplary embodiment of the presentdisclosure.

Referring to FIGS. 2-5, the display panel DP includes a base layer BL, acircuit layer CL, an element layer LEL, and an encapsulation layer ECL.

The base layer BL may be a resin layer containing polyimide (PI),however, the base layer BL may not be limited to a particular material.The circuit layer CL is on an entire surface of the base layer BL. Thecircuit layer CL has a multi-layer structure of an insulating layer, aconductive layer, and a semiconductor layer. The circuit layer CLincludes a pixel circuit with a thin film transistor and signal linesconnected to the pixel circuit.

The element layer LEL is on an entire surface of the circuit layer CL.The element layer LEL may include a light emitting element, for example,an organic light emitting element. The encapsulation layer ECL is on theelement layer LEL to encapsulate the element layer LEL. Theencapsulation layer ECL may have a double-layer structure of an organiclayer/inorganic layer, which is called a thin film encapsulation (TFE).As another example, the encapsulation layer ECL may include only theinorganic layer or only the organic layer. The display panel DP mayinclude an encapsulation substrate and a sealant instead of theencapsulation layer ECL. The sealant may adhere the encapsulationsubstrate to the element layer LEL.

The display panel DP and the protective film PF may be coupled to eachother by the fourth adhesive member AM4. Particularly, a rear surface ofthe base layer BL and the protective film PF may be coupled to eachother by the fourth adhesive member AM4.

The display panel DP may include two areas. That is, the display panelDP may be divided into a bending area BA and a non-bending area NBA. Thebending area BA may include the curvature area CA having the set orpredetermined curvature in the bent state and a facing area FA facingthe non-bending area NBA in the bent state.

The base layer BL and the circuit layer CL may be located correspondingto the non-bending area NBA and the bending area BA. The element layerLEL and the encapsulation layer ECL may be in the non-bending area NBA.

Referring to FIGS. 5 and 6, the groove GR has a shape recessed from thesecond surface RS of the protective film PF and is formed extending inthe first direction DR1.

The protective film PF is located adjacent to the groove GR and furtherincludes a first inner sidewall ISW1, a second inner sidewall ISW2, anda bottom surface IBS, which define the groove GR. The first and secondhydrophobic layers HP1 and HP2 are respectively located on the first andsecond rear surfaces RS1 and RS2 to be respectively adjacent to thefirst and second inner sidewalls ISW1 and ISW2. The first and secondhydrophobic layers HP1 and HP2 extend in the first direction DR1 to beparallel to the groove GR.

Each of the first and second hydrophobic layers HP1 and HP2 may includea hydrophobic material with a water contact angle from about 90 degreesto about 150 degrees or a highly hydrophobic material with the watercontact angle equal to or greater than about 150 degrees. In detail,each of the first and second hydrophobic layers HP1 and HP2 may includea material with a hydrophobic property, such as manganese oxide (MnO2)polystyrene, zinc oxide (ZnO) polystyrene, precipitated calciumcarbonate, carbon nanotube, silica, or fluoropolymer.

Referring to FIGS. 3 and 4, the curvature area CA is between the facingarea FA and the non-bending area NBA in the unbent state, and the facingarea FA faces the non-bending area NBA in the thickness direction DR3 ofthe display module DM in the bent state. In the bent state, a set orpredetermined radius of curvature is defined in the bending area BA withrespect to a bending axis BX extending in the first direction DR1.

Pads of the circuit layer CL (e.g., refer to FIG. 5) may be aligned atone side portion of the facing area FA. The second circuit board FCB isconnected to the facing area FA. The first circuit board MCB and thesecond circuit board FCB face the rear surface of the display panel DPin the bent state.

Because, the groove GR is defined in the curvature area CA of theprotective film PF, a stress occurring in the circuit layer CL duringthe bent state may be reduced.

In the exemplary embodiment of the present disclosure, the protectivefilm PF remains in the area in which the groove GR is defined, however,the present disclosure may not be limited thereto or thereby. That is,as another embodiment, the protective film PF may be removed from thearea in which the groove GR is defined such that the fourth adhesivemember AM4 is exposed to the outside, or the protective film PF and thefourth adhesive member AM4 are removed from the area in which the grooveGR is defined such that a portion of the rear surface of the displaypanel DP corresponding to the curvature area CA is exposed to theoutside. In this case, the term “outside” is defined with respect to thedisplay module DM in an inner space of the electronic device ED ratherthan the outside of the electronic device ED.

The first circuit board MCB and the second circuit board FCB may becoupled to each other by the fifth adhesive member AM5 located betweenthe first circuit board MCB and the second circuit board FCB in thethird direction DR3. The fifth adhesive member AM5 may include aconductive material to electrically connect the first circuit board MCBand the second circuit board FCB. However, in other embodiments, thefifth adhesive member AM5 may merely physically connect the first andsecond circuit boards MCB and FCB, and the first and second circuitboards MCB and FCB may be electrically connected to each other by anadditional conductive member (not shown) provided separately from thefifth adhesive member AM5.

FIG. 7 is a perspective view showing a heating block, according to anexemplary embodiment of the present disclosure, and FIGS. 8A to 8D areside views showing a method of manufacturing a display device, accordingto an exemplary embodiment of the present disclosure.

The heating block HB shown in FIG. 7 includes a metal column having abar shape. The heating block HB may include stainless steel withsuperior strength and durability or may include aluminum or copper witha high thermal conductivity. A length in the direction DR1 in which theheating block HB extends may be longer or shorter than a length in thefirst direction DR1 of the display device DD (e.g., refer to FIG. 2).

As shown in FIG. 8A, a preliminary display device PDD including thebending area BA and the non-bending area NBA is provided. Thepreliminary display device PDD is in a state in which the groove GR(e.g., refer to FIGS. 2 and 3) is not formed in the protective film PF.A preliminary hydrophobic layer PHP is formed on the rear surface RS ofthe protective film PF. In detail, the preliminary hydrophobic layer PHPmay be formed to cover the curvature area CA. A width in the seconddirection DR2 of the preliminary hydrophobic layer PHP is greater than awidth in the second direction DR2 of the curvature area CA.

As an example of the present disclosure, the preliminary hydrophobiclayer PHP may include the hydrophobic material with the water contactangle from about 90 degrees to about 150 degrees or the highlyhydrophobic material with the water contact angle equal to or greaterthan about 150 degrees. In detail, the preliminary hydrophobic layer PHPmay include a material with a hydrophobic property, such as manganeseoxide (MnO2) polystyrene, zinc oxide (ZnO) polystyrene, precipitatedcalcium carbonate, carbon nanotube, silica, or fluoropolymer.

The preliminary hydrophobic layer PHP may be coated on the rear surfaceRS of the protective film PF with a thickness equal to or less thanabout 10 micrometers (μm). The thickness of the preliminary hydrophobiclayer PHP may not be limited to the above value, and the thickness mayvary depending on a process condition or a material of the preliminaryhydrophobic layer PHP. In detail, the process condition may include aheating temperature of the heating block HB, a contact time of theheating block HB, and an applied pressure of the heating block HB.

As shown in FIG. 8B, the heating block HB is aligned with thepreliminary display device PDD. The heating block HB may be disposedabove the preliminary hydrophobic layer PHP. The heating block HB isheated at a set or predetermined temperature after being aligned withthe preliminary display device PDD.

As shown in FIG. 8C, the heating block HB presses the protective film PFto remove portions of the preliminary hydrophobic layer PHP and theprotective film PF. The heating block HB may press the protective filmPF in a state in which the heating block HB is heated at a temperaturehigher than a sublimation temperature of the protective film PF. Forinstance, in a case where a PET film is applied to the protective filmPF, the heating block HB may be heated at the temperature higher thanabout 250° C.

A maximum heating temperature of the heating block HB may be set bytaking into account the base layer BL of the display panel DP. Theheating temperature of the heating block HB may be set to a temperatureat which the protective film PF is sublimated but no thermal damageoccurs to the base layer BL. In a case where the base layer BL includespolyimide, the maximum heating temperature of the heating block HB maybe lower than about 600° C.

The rear surface RS of the protective film PF is divided into the firstand second rear surfaces RS1 and RS2 by the groove GR. The firsthydrophobic layer HP1 is formed on the first rear surface RS1 to beadjacent to the groove GR, and the second hydrophobic layer HP2 isformed on the second rear surface RS2 to be adjacent to the groove GR. Afirst bump BP1 is formed on the first hydrophobic layer HP1, and asecond bump BP2 is formed on the second hydrophobic layer HP2. That is,the first bump BP1 and the second bump BP2 are formed by a plastic resinaccumulated on the first and second hydrophobic layers HP1 and HP2during the sublimation of the protective film PF.

FIG. 8D shows the display device DD from which the heating block HB isremoved. After removing the heating block HB, a process of removing thefirst and second bumps BP1 and BP2 formed on the first and secondhydrophobic layers HP1 and HP2 is performed. Because, the first andsecond bumps BP1 and BP2 are formed while the protective film PF issublimated, the first and second bumps BP1 and BP2 include a hydrophilicmaterial as the protective film PF. Accordingly, when the first andsecond bumps BP1 and BP2 are respectively accumulated on the first andsecond hydrophobic layers HP1 and HP2, an interface is formed betweenthe first bump BP1 and the first hydrophobic layer HP1 and between thesecond bump BP2 and the second hydrophobic layer HP2. An area betweenthe first bump BP1 and the first hydrophobic layer HP1 may varydepending on the water contact angle of the first and second hydrophobiclayers HP1 and HP2. For example, in the case that the first and secondhydrophobic layers HP1 and HP2 include the highly hydrophobic materialwith the water contact angle equal to or greater than about 150 degrees,the area of the interface is reduced compared to that when the first andsecond hydrophobic layers HP1 and HP2 include the hydrophobic materialwith the water contact angle smaller than about 150 degrees.

As described above, when the area of the interface is reduced, the firstand second bumps BP1 and BP2 may be easily removed from the first andsecond hydrophobic layers HP1 and HP2 using a physical force such asair. As an example of the present disclosure, the first and second bumpsBP1 and BP2 are removed by using an air spray device AD in FIG. 8D, butit may not be limited thereto or thereby. When the area of the interfaceis reduced, an adhesive force between the first bump BP1 and the firsthydrophobic layer HP1 and between the second bump BP2 and the secondhydrophobic layer HP2 decreases, and thus the first and second bumps BP1and BP2 may be easily removed from the first and second hydrophobiclayers HP1 and HP2 with a small force, respectively.

As shown in FIG. 8D, inner side surfaces of the fourth adhesive memberAM4 defining the groove GR may be covered by the protective film PF.Accordingly, the inner side surfaces of the fourth adhesive member AM4may not be exposed to the outside.

Referring to FIG. 4 again, a portion (i.e., the curvature area CA) ofthe display device DD corresponding to the groove GR is bent at a set orpredetermined curvature. The first hydrophobic layer HP1 may face thesecond hydrophobic layer HP2.

Although not shown in the figures, as an example of the presentdisclosure, a heat discharge sheet and/or an anti-static sheet may befurther disposed between the first and second hydrophobic layers HP1 andHP2 in the bent display device DD. In addition, as another example, theheat discharge sheet and/or the anti-static sheet may be spaced apartfrom the first and second hydrophobic layers HP1 and HP2 in the seconddirection DR2 and disposed between the first rear surface RS1 and thesecond rear surface RS2 of the protective film PF.

FIG. 9 is a side view showing a display device DD, according to anotherexemplary embodiment of the present disclosure, and FIG. 10 is a sideview showing a bent state of the display device DD shown in FIG. 9,according to an exemplary embodiment of the present disclosure.

Referring to FIGS. 9 and 10, the protective film PF is on the rearsurface of the display panel DP in the display device DD, according toanother exemplary embodiment of the present disclosure. In the presentexemplary embodiment, a groove GR is defined in the protective film PFcorresponding to the curvature area CA. The groove GR corresponds to anarea defined by removing at least a portion of the protective film PF.

The protective film PF includes a first surface FS facing the rearsurface of the display panel DP and a second surface RS opposite to thefirst surface FS. The second surface RS of the protective film PF isdivided into a first rear surface RS1 and a second rear surface RS2 bythe groove GR.

The protective film PF includes a bottom surface IBS (e.g., as shown inFIG. 5), a first inner sidewall ISW1 (e.g., as shown in FIG. 5), and asecond inner sidewall ISW2 (e.g., as shown in FIG. 5) to define thegroove GR. The first inner sidewall ISW1 extends from one end of thebottom surface IBS, and the second inner sidewall ISW2 extends from theother end of the bottom surface IBS. A first sub-groove SGR1 is formedbetween the first inner sidewall ISW1 and the first rear surface RS1,and a second sub-groove SGR2 is formed between the second inner sidewallISW2 and the second rear surface RS2. In detail, the groove GR islocated between the first and second sub-grooves SGR1 and SGR2.

A first bump BP1 is formed in the first sub-groove SGR1, and a secondbump BP2 is formed in the second sub-groove SGR2. According to theexemplary embodiment of the present disclosure, the first and secondbumps BP1 and BP2 are respectively accommodated in the first and secondsub-grooves SGR1 and SGR2. Accordingly, a height of the first and secondbumps BP1 and BP2 protruded from a horizontal surface parallel to thesecond surface RS of the protective film PF may be reduced compared withthat when the first and second sub-grooves SGR1 and SGR2 are not formed.

Referring to FIG. 10, the portion of the display device DD correspondingto the groove GR is bent to have the set or predetermined curvature. Inthis case, the first sub-groove SGR1 may face the second sub-grooveSGR2, and the first bump BP1 may face the second bump BP2.

As described above, because the protruded heights of the first andsecond bumps BP1 and BP2 are reduced, interference due to the first andsecond bumps BP1 and BP2 may be reduced even though the first and secondbumps BP1 and BP2 face each other in the bent state of the displaydevice DD.

Although not shown in figures, as an example of the present disclosure,a heat discharge sheet and/or an anti-static sheet may be furtherdisposed between the first and second bumps BP1 and BP2 in the bentdisplay device DD. In addition, as another example, the heat dischargesheet and/or the anti-static sheet may be spaced apart from the firstand second bumps BP1 and BP2 in the second direction DR2 and disposedbetween the first rear surface RS1 and the second rear surface RS2 ofthe protective film PF.

FIGS. 11A-11C are cross-sectional views showing a method ofmanufacturing the display device shown in FIG. 9, according to anexemplary embodiment of the present disclosure, FIG. 12A is aperspective view of FIG. 11A, according to an exemplary embodiment ofthe present disclosure, and FIG. 12B is a perspective view of FIG. 11C,according to an exemplary embodiment of the present disclosure.

Referring to FIGS. 11A and 12A, a preliminary display device PDDincluding a bending area BA and a non-bending area NBA is provided. Thepreliminary display device PDD is in a state in which the groove GR(e.g., refer to FIGS. 9 and 10) is not formed in the protective film PF.First and second preliminary sub-grooves PSGR1 and PSGR2 are formed inthe second surface RS of the protective film PF. In detail, the firstand second preliminary sub-grooves PSGR1 and PSGR2 may be formed tooverlap with the curvature area CA.

As an example of the present disclosure, a distance d1 between a centerportion (hereinafter, referred to as “first center portion CP1”) of thefirst preliminary sub-groove PSGR1 and a center portion (hereinafter,referred to as “second center portion CP2”) of the second preliminarysub-groove PSGR2 is equal to a width of the curvature area CA. However,according to embodiments, positions of the first and second preliminarysub-grooves PSGR1 and PSGR2 may be set under a condition in which awidth w1 of the second surface RS between the first and secondpreliminary sub-grooves PSGR1 and PSGR2 is not greater than the width ofthe curvature area CA and the distance d1 between the first centerportion CP1 and the second center portion CP2 is not smaller than thewidth of the curvature area CA.

The first and second preliminary sub-grooves PSGR1 and PSGR2 may beformed through, for example, a blanking process, but it may not belimited thereto or thereby.

The first and second preliminary sub-grooves PSGR1 and PSGR2 have ashape formed by recessing a portion of the protective film PF from thesecond surface RS and extend in the first direction DR1.

Although not shown in the figures, as another exemplary embodiment, thefirst and second preliminary sub-grooves PSGR1 and PSGR2 may be formedin a dot form. In addition, a plurality of first preliminary sub-groovesPSGR1 spaced apart from each other in the second direction DR2 and aplurality of second preliminary sub-grooves PSGR2 spaced apart from eachother in the second direction DR2 may be formed on first and second rearsurfaces RS1 and RS2 of the protective film PF, respectively.

Referring to FIG. 11B, the heating block HB is aligned with thepreliminary display device PDD. The heating block HB may be disposedabove the preliminary hydrophobic layer PHP. The heating block HB isheated at a set or predetermined temperature after being aligned.

As shown in FIG. 11C, the heating block HB presses the protective filmPF to remove portions of the preliminary hydrophobic layer PHP and theprotective film PF. The heating block HB may press the protective filmPF in a state in which the heating block HB is heated at a temperaturehigher than a sublimation temperature of the protective film PF. Forinstance, in a case where a PET film is applied to the protective filmPF, the heating block HB may be heated at the temperature higher thanabout 250° C.

A maximum heating temperature of the heating block HB may be set bytaking into account the base layer BL of the display panel DP. Theheating temperature of the heating block HB may be set to a temperatureat which the protective film PF is sublimated but no thermal damageoccurs to the base layer BL. In a case where the base layer BL includespolyimide, the maximum heating temperature may be lower than about 600°C.

A portion of the protective film PF between the first and secondpreliminary sub-grooves PSGR1 and PSGR2 is sublimated, and thus thegroove GR is formed between the first and second preliminary sub-groovesPSGR1 and PSGR2. According to the positions of the first and secondpreliminary sub-grooves PSGR1 and PSGR2, the first and secondsub-grooves SGR1 and SGR2 may be formed in the same shape as the firstand second preliminary sub-grooves PSGR1 and PSGR2, or portions of thefirst and second preliminary sub-grooves PSGR1 and PSGR2 may be formedas the first and second sub-grooves SGR1 and SGR2.

A portion of the protective film PF, which is melted during thesublimation of the protective film PF, may be collected in the first andsecond sub-grooves SGR1 and SGR2. Accordingly, the melted portion of theprotective film PF moves to the first sub-groove SGR1 to form the firstbump BP1 and moves to the second sub-groove SGR2 to form the second bumpBP2.

In this case, a crystal structure of the first and second bumps BP1 andBP2 is different from a crystal structure of the protective film PF. Thecrystal structure of the first and second bumps BP1 and BP2 may bedenser than the crystal structure of the protective film PF. Forexample, the first and second bumps BP1 and BP2 may have a face-centeredcubic crystal structure, and the protective film PF may have abody-centered cubic crystal structure.

As shown in FIG. 12B, the first and second bumps BP1 and BP2 extend inthe first direction DR1 along the first and second sub-grooves SGR1 andSGR2.

Although the exemplary embodiments of the present invention have beendescribed, it is understood that the present invention may not belimited to these exemplary embodiments but various changes andmodifications can be made by one ordinary skilled in the art within thespirit and scope of the present invention as hereinafter claimed.

Therefore, the disclosed subject matter may not be limited to any singleembodiment described herein, and the scope of the present inventiveconcept shall be determined according to the attached claims.

What is claimed is:
 1. A display device comprising: a display panelcomprising a non-bending area and a bending area configured to bend fromthe non-bending area, the bending area comprising a curvature area witha curvature and a facing area configured to face the non-bending area; aprotective film on a rear surface of the display panel, the protectivefilm comprising a first surface configured to face the rear surface ofthe display panel and a second surface opposite to the first surface,the protective film having a groove corresponding to the curvature area;an adhesive member between the protective film and the display panel;and a hydrophobic layer on the second surface of the protective film,the hydrophobic layer comprising a first hydrophobic layer at a firstside of the groove and a second hydrophobic layer at a second side ofthe groove, wherein the first hydrophobic layer and the secondhydrophobic layer face each other when the facing area faces thenon-bending area.
 2. The display device of claim 1, wherein the secondsurface of the protective film comprises a first rear surface and asecond rear surface and the groove is between the first and second rearsurfaces, and the protective film further comprises a first inner sidesurface extending from the first rear surface to define the groove and asecond inner side surface extending from the second rear surface todefine the groove.
 3. The display device of claim 2, wherein the firsthydrophobic layer is on the first rear surface, the first hydrophobiclayer being adjacent to the first inner side surface; and the secondhydrophobic layer on the second rear surface, the second hydrophobiclayer being adjacent to the second inner side surface.
 4. The displaydevice of claim 3, wherein the groove extends in a first direction, andeach of the first and second hydrophobic layers extends along the firstdirection.
 5. The display device of claim 1, wherein the hydrophobiclayer comprises one of manganese oxide (MnO2) polystyrene, zinc oxide(ZnO) polystyrene, precipitated calcium carbonate, carbon nanotube,silica, and fluoropolymer.